Hi Garth.
My car has that same heater valve setup, it’s possible the design came from John’s car.
I’m traveling, or I could provide you more information.
The valve allows the water to recirculate through the heater passages back to the water pump, and bypass the heater matrix in the console.
It’s a standard 4 Seasons, or Everco unit - I believe it was only about $20 or so.
It’s operated by a cable to the front slider.
I wrote a couple articles in the POCA Newsletter on how Wade and I implemented it. Anyone who is interested, PM me your email address, and I’ll send the articles, they are too big to attach here.
Rocky
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